Various methods are known in the art for providing enough pressure on the face seal of an electrical connector to prevent, e.g., dirt or moisture from fouling or otherwise damaging the pin and socket contacts of the connector or shorting adjacent contacts. In most screw-type circular connectors there is employed a coupling ring which is tightened down hard enough to place the seal face, e.g., on the portion of the connector having the pin contacts under sufficient pressure against the socket insulator in the other portion of the connector to accomplish the desired sealing. One or both of the sealing faces typically have a resilient material covering all or portions of the faces, which provides the sealing effect when put under pressure by the faces being forced against each other. Over the life of the connector, as the resilient material takes a set, the sealing pressure on the faces will become less effective in providing the required sealing. This results in the coupling ring being required to be tightened further in order to maintain the desired sealing.
On certain connectors, e.g., a Series IV Mil-38999, manufactured by the assignee of the present invention, the coupling ring is designed to be rotated a specific amount during mating. Subsequent loss of sealing pressure at the contact faces due, e.g., to the elasastomeric material taking a set over time, cannot be corrected by futher tightening of the coupling ring in such a connector.
In the past, it has been the practice in such connectors, as is shown, e.g., in U.S. Pat. No. 4,277,125 (assigned to the assignee of the present invention, the disclosure of which is hereby incorporated by reference) to provide an internal spring loaded coupling nut. The nut is positioned intermediate the coupling ring and the driven portion of the connector driven by the coupling ring. It is threaded to both and rotation of the coupling ring drives the driven portion of the connector into the mating (and sealing) position. It will be understood that the driven portion of the connector may be, as shown in the '125 patent referred to above, the plug portion containing socket contacts. But the plug portion is so defined by connection because it contains an insert, having the contact containing face, which fits into an insert in the other, receptacle, portion of the connector. Either of the plug portion and receptacle portion would be the driven portion and either could contain socket contacts with the other than containing pin contacts, or perhaps corresponding pin in socket contacts could be contained in both. Whatever the construction of the driven portion and its associated other portion of the connector, there has been utilized in the past a wave spring coacting with the coupling ring and the coupling nut to bias the driven portion of the connector into face sealing engagement with the other portion of the connector, by exerting a spring force in the mating direction on the coupling nut after the coupling ring is rotated to the fully mated position. This spring biasing accounts for changes in the effective face sealing over the life of the connector.
While effective in maintaining the face seal, the prior arts connector of the '125 patent, employing the spring biased coupling nut has several drawbacks. For one, the '125 patent demonstrates that the construction is costly to manufacture. The various alignment lands and grooves, keys and keyways, necessary for interfacing the coupling ring, coupling nut and driven portion of the connector, as an example, increase the overall manufacturing cost of the connector. In addition, the utilization of a coupling nut, whether spring biased or not, increases the overall diameter of the connector. This may prohibit its use, e.g., where multiple connectors are grouped together in a limited space.
Recognizing the need for an improved face seal pressure device for utilization in connectors employing a coupling ring, especially one where the coupling ring, in order to guarantee the operator will not over-torque the connector, is one which by design cannot rotate more than a certain amount. The object of the present invention is to provide such a face seal pressure device. A feature of the present invention is to directly couple the threads of the coupling ring and threads on the driven portion of the connector, without a coupling nut, and to insert a spring means intermediate at least one of the threads on the coupling ring, and the driven portion of the connector. A typical split wave spring may be used as may be the split wave spring specifically designed for the present invention, having corrogated legs. Another feature of the invention is to provide a means for preventing the spring means from slipping out of the threads by, e.g., providing notches on the particular thread facing the wave spring legs to receive the end of the respective leg.
The above described features and advantages of the present invention have been given rather broadly in order that the more detailed description given below may be better understood and the contribution to the art better appreciated. These and other features of the invention will be apparent to those skilled in the art by reference to the detailed description below in conjunction with the drawing, in which like reference numerals are used to designate to like elements and in which: